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best way to flatten case back ?


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Yesterday I realized that probably, while mounting the new crystal to my GMT I may have unflattened the case back as in the picture.

I used this kind of screw press to do the job 

 

potenza-forza-chiudi-casse-posa-vetri-a-

 

and now the case back looks like this, a little pressed inside. The rotor is not affected and is moving freely, my idea is to remove the back and use the same press to try get the thning more flat. What do you think? I wasn't aware this stainless steel back could be so easily deformed. 

 

IMG_0909.JPG

Edited by chriz74
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Yehooooo . As ro63rto saying it would have been best to remove the caseback and movement to do that? You need to find something that has the same shape as the caseback. To press from the inside with?  To even it out? Sure can be done. But!!

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23 minutes ago, ro63rto said:

 

Never had this problem as I've ALWAYS removed movement and hence caseback to fit crystal.

 

Imagine crystal breaks. Bang goes your dial etc.

That is not possible with a GMT crystal. That's not a press in crystal. It's hold by an outer ring that you press down with an hollow adapter. You don't touch the crystal at all while pressing.

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Yikes - sorry to see that this happened. This is not my area of expertise, but I would be very hesitant to attempt to repair this yourself. I can imagine all sorts of ways to make this problem a whole lot worse.  If you do feel compelled, I would first repeat the process you did on a junk case and attempt the repair on that before messing with the GMT. Good luck!

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2 hours ago, chriz74 said:

That is not possible with a GMT crystal. That's not a press in crystal. It's hold by an outer ring that you press down with an hollow adapter. You don't touch the crystal at all while pressing.

Nevertheless you press in the case with the case back removed. By the way that press is a snap-in case back press, which can be used with some crystals too but only the easy ones. I think your case back can spring back in place but I'm not sure if without any permanent deformation.

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26 minutes ago, jdm said:

Nevertheless you press in the case with the case back removed. By the way that press is a snap-in case back press, which can be used with some crystals too but only the easy ones. I think your case back can spring back in place but I'm not sure if without any permanent deformation.

I don't get what You are saying. The case back is screw-in not snap-in . Tomorrow I'll see if I can get it back in shape.

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Just now, chriz74 said:

I don't get what You are saying. The case back is screw-in not snap-in . Tomorrow I'll see if I can get it back in shape.

I'm saying:   that press is a snap-in case back press.

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20 minutes ago, jdm said:

I'm saying:   that press is a snap-in case back press.

Well ok, anyway I used it to snap in a crystal on a Bulova with ease and to press the ring holding the GMT crystal. I didn't realize the SS is easily deformed. However it's not a big deal.

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That is not possible with a GMT crystal. That's not a press in crystal. It's hold by an outer ring that you press down with an hollow adapter. You don't touch the crystal at all while pressing.

And if the crystal is flawed in any way it can still shatter sending glass particles and glass dust into your movement.

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I would use the same technique I use on pocketwatch cases that have dents. That is use a wooden dowel that have the edges rounded down, sort of like a baseball bat in miniature. Then  with your hands gently push and roll and push some more, until it's back in shape. Make sure the case is on a hard smooth surface and be patient "Don't Rush It"     

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13 hours ago, ro63rto said:

And if the crystal is flawed in any way it can still shatter sending glass particles and glass dust into your movement.

Can't happen. It's plastic + the press doesn't touch it at all. The press presses the outer ring that holds it. Please google it.

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